rescue call
n. A call to a cell phone placed at a prearranged time to give the person being called an excuse to end a date or other social engagement.
The SOS service just shows the way things past come back and haunt you. And it's funnier that even technology is like that. In an earlier generation, people set up a friend or colleague to make the rescue call.
—N. Nagaraj, “Dial SOS for that exit line,” The Hindu, March 07, 2005
The peak time for dates from hell in New York City is Friday at 8 p.m. — judging by the cell phone calls delivering emergency excuses to bolt.

Truth is, they're fake "rescue" calls — now being offered by two cell phone providers, Cingular Wireless and Virgin Mobile USA. In an era of Internet-set dates, it's just customer service — a hip way to wiggle out of an uncomfortable encounter.
—“Via cell, help's on the way for bad dates,” The Associated Press, August 08, 2004
2002 (earliest)
The Virgin Mobile will provide quirky functions aimed at the youth market, the company said. Callers will be able to programme their telephones to send them a "rescue call" and a message, which will provide them with a plausible escape from a blind date gone wrong.
—Abigail Rayner, “Virgin targets US mobile market,” The Times (London), June 21, 2002
Have you ever been on a bad date and wished someone would call you with some urgent task that required your immediate attention? Wish no more: Cellular providers Cingular Wireless and Virgin Mobile USA offer rescue call services that ring your cell phone at a preset time and supply you with a "script" to make it appear that you've received an emergency call. (Cingular's service is called, memorably, Escape-A-Date.)